Method and apparatus for distillation of hydrocarbons



C. D. GARD Aug. 29, 1933.

METHOD AND APPARATUS FOR DISTILLATION OF HYDROCARBONS Filed May 30, 1930INVENTOR. 34 %are .0. Gard BY /2 Mad M11 TTORNE Y.

Patented Aug. 29, 1933' N ED LTM' E'S v v 11,324,602 1 METHOD ANDAPPARATUS FOR DISTILLA- a 5 TION or HLYDROCARBONS C larerDa Gard, LosAngeles', Calif assignor to Union Oil Companyof California, Los Angeles,

Calif a corporation of California Application may 30,4193). Serial No.457,656 7 5 Clain sQ (01.196585) 4' This invention relates todistillation method and apparatusandis. directed more particularly tosteam distillation of oil in which the steam is directly introduced intothe oil and the oil is.

' agitated thereby.

'I have found that while operating either at constant or increasingtemperatures it .is ;high-' 1y. advantageous to keep the oil and thesteam -in:constant and adequate contact in order to vaporizethe-maximum. percentage of oil vapor- ;iz'able underthe-conditions.employed;

.iA. difficulty] is. ordinarily I encountered 'inithe ].distillation ofoil due to .the' fact that thelighter vapors volatilized from the oilbody carry over 1011 fractions heavier thanthose desired .inthat'.pai'ticular c'ut." Also, the unvolatilized oil re- -maining in thestill may yet contain lighter oil fractions" which desirably; should bexxdistilled .overlwith the other vapors. .Ihave found that by refluxing.imdesirable heavy oils back into the oil body and by contacting the oilbottoms. with ,j

the steam .employed' as adistillation aid, either at aconstanttemperature or at increasing'temperatures. An. additional.object is 'tocpro'vid'e means for the return offreflux and the circula-:tion ofstill' bottoms. All 'ofz these objectspare for the purpose ofdistilling oil to obtain vapors free :from undesirable heavy fractions'and to "insurextotal vaporization of a all fractions "dc- I c Ineitherevent; it-must be'given aconformation sired in the vapor statewithout-the danger of *local overheating.

. More specifically stated/the invention comprises "a distillingapparatus including an. oil still concentric steam pipes woundverticallyto form baflles which act to direct the course of oil currentsproduced by steam which isinjected into withir'itthe annular spacebetween ,;the {inner 'apparatus in. which reflux condensate obtained 1from the vapors rising froni the oil bodyand/or unvolatilized oilobtained from the oil bottoms .may causedgtjo re enter intotlie oil 7heating coil and theouter heating'coil-L The in -Q; fvention furthercomprises a steam distillation middle area of i the cylindrical" spacefoutlined f maintained in circulation b means of the; afore- 3 1 saidbaflles and steam. 1 The invention-also comprises the method ofdistillation wherein our.

rents. within the oil body rare induced, lay-"flow of steam therethroughand wherein the sa'id' E currents arechanged indirection; by a secondfstream of steam,the .oilmeanwhilebeing-heated h by contact'withinternal heating means.

- nth acco anyin d aw n her n -",'85 ferred embodiment of the inventionisldisclosed "byway of illustration: I

Fig. l isa vertical section showing anoiljdis-f tillation columnconstructed according to; the

present invention; and. i

, 0 'Figs. 2 and 3 arecross-sections through the distillation ,1 column:and are taken respectively sents a shell ,of a rvertical still connected-with oil conducting pipe .2' 'Whi0hbranches into inlet pipe 3controlled byvalve;4'andinlet'pipe 5 con-.

trolled by valve ;Still 1 is further provided with vaporoutletilcontrolled by valve. 10 and residuum I outlet ll controlled .by' valve12.: Below the nor-,

\ing "steam inletl? controlled ibyzva-lve -1'8 and out- 35 'let.;l9controlled, by valve 203' comprisesa pipe vertically; coiled to form abaflle which. acts v.to direct the course of, oil-currentsproduced bysteamenteringthrough jet 30 to be described be low. Coil 116 may be,tightly; woundin order'to Q forma substantially solidcylindricalqwalL-oritauj may notbe necessary to windit as tight as this.I

sufiicientto forma baflie' for the'purpose of directing oil currents inthe body ofoil' in a manner .to ibe describedbelow.

adapted to hold a body of oil and containing 'two V pipe 24 controlledby valve 25 and outlet 26 con- The outer heating coil 21 comprises steaminlet I trolled by valve 27.' Heating coil" 21 may be more looselygwound than coil I6 in order to allowat least a partial flow of oilbetween the coils. Steam= jet 30 in its preferredform-islshown indetailin Fig.1i3. It comprisesitwo c'oncentr-ic'pipes' Bland 32connected bypipesf33fsteam in1et ;-3 4controlled by valve 35 connectswith thejinner pip'e32 which is p'erforatedon'its'uppr s e.'; Outerpipe31*is li ewis perrcrageq;. 71; periorati onsfon the inner .je't ar'e, soarranged that steam jettingfrom them will pass through "approximatelythe no 7 or other heating fluid is passed through heating 7 pipes 31 and32 respectively can be individually controlled. If additionally desired,either one of these streams of steam may be totaliyishut, off

depending upon the exigencies in the distillation of any particularoil.. I a V The upper portion of still 1 comprises a reflux sectioncontaining reflux plates provided with bubble caps 41 and overflow pipes42 disposed in therusual manner. may extend to a point above oil levelA--A or it may depend into the oil body'in the manner as I V :of innerheating coils 16, thereby aiding'in' the circulation of the-oil body aspreviously a de shown. Deflector 44 is provided in orderto give thedesired directional flow to the incoming oil. For circulating the-oil:bottoms, pipe is provided, connected with still 1 near the bottomthereof and also' with the refluxing section thereof. In order tocirculatethe'oil from the bottom of the still through line 50 back intothe still,

thereis provided steam or oil inlet 51 terminating valve 52. V I

In employing this system 'for the distillation of oil, still 1 is filledwithoil to the level A-A, maintained during the course of the operation.The

steam ejected from'the, perforationsin the upper oil may enter from .asource not shown through pipes 2, 3and 5, valves 4 and-6 being open.'Steam coils l6 and-21, the steam enteringthrough inlets 1'7 and 24,respectively and leaving the coils through outlets 19 and 26,respectively. Steam is 30.- The steam which isjetted through theperfof-ration's in pipe 32,'si tuated in approximately the heatingmeans. This downward flowing current of oilwithin the oil body thencauses the oil to.

flowbelow coil 16. The ascending'current-of part'of outer steam pipe 31which-is situated so thatthe steam flows-between the inner heating coils16 and the outer heating coils 21 assists-in drawing the oil :from theinner chamber into the annular .chamber between coils 16 and 21. Theetting action last mentioned thereby reverses the flow of the oil in theoil body and causes an up- :ward circulation which forces .the oilbetween the any particular oil. Due to the prolonged, andintimatecontact between the oil, the steam and theheating coils auniformity oftemperature .ma y be "maintained within. the oil body-and a' maximum-of-.,products desired in the vapor state may 'be'volatilized therefromwithout danger of local overheating. e 7

As the .oil is 'volatilizedg the vapors pass upwardly through'thebubble-caps 4 situated on The bottom 1 overflow pipe 43 'vided withoutdeparting from also introduced directly into the oil through jet thereflux plates 40 in the usual manner. Fresh oil may becontinuouslyintroduced into still 1- caused to enter upon either or both of thereflux plates 40 above which these inlets are directly situated,depending upon the degree of refluxing desired. The fresh oil and refluxcondensed from the vapors flow downwardly from the reflux plates '40through overflow pipes 42 in counter-current with ascending vapors inthe usual manner. The oil on the lowest reflux plate 40 is then directeddownwardly through overflow pipe 43. If the latter does not depend intothe body of oil, the oil descending therethrough merelydropsiupon the.

scribed- Other types of deflectorsx-may b'eprothe spirit of theinvention. y

The 011 bottoms may still contain some lighterfractions which it isdesired should be vaporized. In order to accomplish the totalvaporization of these lighter fractions, the bottoms are recirback intothe refluxing-' section of the. still. 'In

order to forceithe oil from the bottomof the still upwardly through pipe50 back into the 1 still, steam or the like may be injected intovertical pipe S'O'through injector 53 connected withsteamtfio supplypipe 51 controlled by valve :52. In place 'of steam, a portion of theoil charge'may be fed into the still 1 through line5l', andinjector 53The same result is thereby producedyi". e.

1 lifting the oil bottoms through pipe .50 for recirculation.

Due to the scrubbing *action .onthe vapors heavy undesirableconstituentswill be removed within the refluxing zone previouslydescribed, Y

from the vapors and will be refluxed into the oil;

body. Due to the recirculation of the oil 'bot- 7 toms and-totheconstantand adequate contact of the oilysteam, and heating coils, as previouslydescribed, substantially-all of the products desired in the vapor statewillbe volatilized from w the'oil. Vapors from the still pass'throughpipe 9 controlled by valve 10 into suitable condensers or the like,notshown. 'Residuum from still '1 exits through pipe 11 controlledibyvalve 12 .to suitable storage or the like,not shown.

The pressures and temperatures. employed this devicev depend entirelyupon the character ofsthe oil stock introduced into the still and theboiling points of the fractions which are to I be separated by thedistillation. The. amount of g} refluxing is'likewise dependent upon.these conditions.

It is tobe understood that the above disclosures are considered merelyas illustrative and not as tiliation chamber and additionallyfunctioning as .a-cu'rrent directing baffle, asecond heating coil,spaced fromand disposed around said first mentioned coil, and means toinduce circulation of the oil undergoingdistillation in 'suchamannerthat oil Within the distillation chamber 'iscaused .1 9 W downwardlyalong the inner periphery apparatus, a vertically dis-' r of the closelywound coil and thence upwardly between the two coils.

-2. In distillation apparatus, a vertically disposed, closelywoundheating coil defining a distillation chamber and additionallyfunctioning as a current directing baffle, a second heating coil,

spaced from and disposed around said first mentioned coil, and means forinjecting steam into the distillation chamber so that the oil undergoingdistillation is caused to flow downwardly along the inner periphery ofthe closely wound coil and thence upwardly. between the two coils.

3. In distillation apparatus, a vertically disposed, closely woundheating coil defining a distillation chamber and additionallyfunctioning as a current directingbafile, a second heatingcoil, spacedfrom and disposed around said first mentioned coil, and means forinjecting steaminto the space between the two coils so that the oilundergoing distillation is caused 'to flow down-' wardly along the innerperiphery of the closely wound coil and thence upwardly between the twocoils.

4. In distillation apparatus, a vertically disposed, closelywoundheating coil defining'a'distillation chamber and additionally.functioning as a current directing baflle, a secondheating coil,"

spaced from and disposed around said first mentioned coil, means forinjecting steaminto the distillation chamber and means for injectingsteam intothe space between the two coils so that the oil undergoingdistillation is caused to flow downwardly along the inner periphery ofthe closely wound coil and thence upwardly between'the'two coils.

5. A method of steam distilling oilwithout substantial cracking thereofcomprising inducing a down-flowing current of oil along the periphery ofa heating coiland within a body of oil by an ascending stream of steam,deflecting the direction of said down-flowing current by a second,ascending stream of steam so that the oil is

